This invention relates to an arrangement for absorption of electromagnetic radiation and the transformation of electromagnetic radiation to heat energy, kinetic electroenergy, ionizing energy and other forms of energy. The invention is particularly directed to the provision of components for determining a function, such as photoelectrical detectors, solar energy converters and resonance absorbers.
Arrangements for the absorption of electromagnetic radiation are known having material composition, surface properties and/or inner structure which make them capable of absorbing a part, as large as possible, of the radiant energy striking the apparatus. Based upon the high reflection occurring at the interfaces of the absorbing media, the yield of energy to be absorbed is rather small because, following the energy principle, the reflected part of radiation is subtracted from the radiation entering the absorbing material. Methods for the demirroring of surfaces, for instance of metals with appropriate optical surfaces, effecting an increase of the penetrating part of radiation, are known. Since the absorption of electromagnetic radiation in metals occurs in path-lengths of approximately 10.sup.-4 to 10.sup.-5 cm and in other less absorbing substances in even longer distances, the absorbing materials must have thicknesses of at least that order of magnitude in order to provide efficient absorption.
Arrangements are also known where increased absorption is obtained using very thin layers. In other words, more radiation transparent layers are provided, these layers being thinner than the above-mentioned order of magnitude. An increase of absorption in these arrangements is obtained by the addition of non-absorbing appropriately dimensioned, extended and/or layered media, however having relatively low efficiency due to the relatively high remaining transparency, as required by theoretical principles.